The present invention broadly relates to a drive system for a self-propelled harvesting machine. Such drive systems comprise a drive engine, such as an internal combustion engine, a transfer gearbox, which is driven by the drive engine and has a first driven pulley, the first driven pulley disposed on a drive shaft to drive, via a belt, at least one first drive pulley of a working mechanism, such as a cutting cylinder. The drive system also comprises at least one first and one second hydraulic unit, designed as a hydraulic pump, for driving other working mechanisms, e.g., of a front attachment and an intake conveyor mechanism of the self-propelled harvesting machine.
In such a drive system, the first and the second hydraulic pumps are each driven, e.g., by toothed gearing operatively connected to the transfer gearbox or using a drive pulley driven by the belt.
Alternatively, the two hydraulic pumps are driven by an intermediate drive shaft that is integrated into the drive system or by an additional drive pulley. The intermediate drive shaft and the drive pulley drive the first hydraulic pump. The first and the second hydraulic pumps are interconnected by the toothed gearing or are disposed one behind the other such that the first hydraulic pump drives through to the second hydraulic pump, which is disposed downstream of the first hydraulic pump.
A disadvantage of these known drive systems is that, in an arrangement of the hydraulic pumps disposed one behind the other, in which the first hydraulic pump drives through to the second hydraulic pump, the selection of hydraulic pumps that can be used is limited by manufacturer specifications for this operating arrangement.
According to the alternative embodiment of a drive system, in which the drive power for the particular hydraulic pump is drawn separately from the drive train, additional components are required, such as a V-belt pulley, toothed gearing, an intermediate drive, an intermediate drive shaft and the like.